The present invention relates to a cleaning mechanism for a wet-shaving razor unit and, more particularly, to a one-push cleaning mechanism for a flexible, twin-blade, wet-shaving razor unit.
The use of twin-blade, wet-shaving razor units, such as disposable razors and cartridges, has become quite common. The blades in these razor units are fixedly spaced apart from one another to create a desired blade geometry. During shaving, various forms of debris, e.g., cut whiskers, shaving cream, soap, etc., can become lodged within the space between the blades. Because such shaving debris may detract from the effectiveness of the shave, various mechanisms have been suggested for removing the debris from this space during and/or after shaving.
For example, U.S. Pat. Nos. 3,972,114, 4,047,296, 4,226,019, 4,205,437, and 4,344,227 disclose various cleaning mechanisms for removing the debris that becomes lodged between the blades of a twin-blade razor unit during shaving. However, these cleaning mechanisms were designed for use with rigid, twin-blade, wet-shaving razor units and, accordingly, are not suitable for use with the recently-introduced, flexible, twin-blade, wet-shaving razor units.
In particular, the rigid, twin-blade, wet-shaving units of the prior art are typically designed with four securing posts that pass through the blades and connect the cap portion to the seat portion. Because these razor units are of a rigid design, the use of four securing posts is sufficient to maintain the components of the razor unit in the desired blade geometry during shaving. At the same time, the use of only four securing posts leaves the central portion of the razor unit free to accept a cleaning mechanism. For example, the razor unit disclosed in U.S. Pat. Nos. 4,205,437 and 4,344,227 are both rigid razor units that employ four securing posts to interconnect the components and maintain the desired blade geometry.
Recently, however, a flexible razor unit has been introduced into the commercial market. This flexible razor unit represents a significant advance in the shaving field in that the razor unit is able to flex in response to forces encountered during shaving, thereby enabling the razor unit to conform to the natural contour of the surface being shaved, which, in turn, brings a greater portion of the blades into effective, cutting contact with the surface being shaved. However, in this recently-introduced flexible razor unit, it is necessary to employ a centrally-fixed securing post to ensure that the razor unit maintains its blade geometry as the unit is flexed.
An early design of a flexible razor unit (as described in U.S. Pat. No. 4,854,043) employed three securing posts, including one centrally-fixed securing post. It was discovered, however, that the use of only three posts was insufficient to ensure that the desired blade geometry was maintained during flexing of the razor unit while shaving. An improved configuration employing five securing posts, including one centrally-fixed securing post, was subsequently designed.
This improved configuration, which employed a rectangular spacer to space the blades apart from one another, was designed and manufactured with a relatively small height and weight, a characteristic possessing desirable commercial attraction. In other words, the commercial market has come to associate a "slim" cartridge with one that provides a desirable shave, With respect to cleaning mechanisms, the need to maintain this "slim" configuration presents substantial difficulties in designing a suitable cleaning mechanism capable of being used in the existing, flexible wet-shaving razor unit.
As mentioned, the centrally-fixed securing post is an important component of the flexible razor unit. The inclusion of such a post, however, presents a substantial challenge to the design of a suitable cleaning mechanism. In particular, the ejector bar of the cleaning mechanism must be capable of forward/rearward movement in the presence of the centrally-fixed securing post. This means that both the actuator and the biasing return members must be operable with respect to this fixed post. Additionally, the cleaning mechanism must be designed to maintain the "slim" configuration of the razor unit.
Of the prior art references mentioned above, neither the cleaning mechanism disclosed in U.S. Pat. No. 4,344,227 nor the cleaning mechanism disclosed in U.S. Pat. No. 4,205,437 are employable with a razor unit having a centrally-fixed securing post. The other cited references disclose various cleaning mechanisms providing less desirable designs.
For example, U.S. Pat. No. 3,972,114 discloses a cleaning mechanism having a "saw-like" configuration and which is positioned between the blades of a twin blade razor unit. During and/or after shaving, the cleaning mechanism is operated by moving it from side to side, i.e., in a direction parallel to the blade edge. This operation requires two hands--one to hold the razor unit and the other to operate the cleaning mechanism. It is stated in the patent that this action will dislodge the debris trapped between the blades during shaving.
Next, U.S. Pat. Nos. 4,226,019 and 4,047,296 both disclose rectangular-shaped cleaning mechanisms that surround a smaller rectangular-shaped spacer. Such a design is disadvantageous when employed with flexible razor units because the rectangular spacer (having securing pins passing therethrough) significantly reduces, if not eliminates, the flexibility of such unit. As is well-known in the art, the linear distance between the ends of a flexible razor unit decreases as the unit is flexed. The design of the spacers in the above-mentioned references would limit or, not allow, the individual components of the razor units to move transversely with respect to one another as the units are flexed. Additionally, the design provides a less desirable means of biasing the ejector bar to the retracted position.
It would therefore be desirable to provide a cleaning mechanism for use in a "slim" flexible, twin-blade, wet-shaving razor unit having a centrally-fixed securing post. This cleaning mechanism must also be of such a design that it does not unduly reduce the flexibility of the device.